This invention relates to a visual aid apparatus which is particularly useful for viewing objects or structures beneath the surface of water. The particular embodiment disclosed in this application is of an apparatus for use with a swimming pool vacuum cleaner to permit the user to clearly see the bottom of the pool so that the bottom of the pool can be quickly and efficiently cleaned by permitting the user to see where the vacuum nozzle should be directed.
As is well known, flat water forms a relatively transparent surface and, depending on the turbidity of the water, will permit clear vision to a substantial depth. However, disturbance on the water surface caused by wind or objects in the water cause light reflections and undesirable light refraction which makes it virtually impossible to see beneath the surface of the water.
In principle, it is known that subsurface vision can be greatly improved by creating a perfectly flat surface on the water. For example, a glass-bottom boat accomplishes this by creating a viewing window beneath the surface of the water. Likewise, one wearing a scuba mask can greatly improve underwater vision by placing the clear lens of the mask beneath the surface of the water.
However, to the best of applicant's knowledge, this principle has never been applied to assist in carrying out utilitarian functions in swimming pool maintenance or spearfishing in shallow water. Therefore, this invention is directed to a visual aid apparatus which is particularly suited for these purposes.